Addressing thermal effects in integrated circuits (ICs) is an ongoing challenge. The performance of an IC varies as temperature changes, and often the resulting variation is undesirable. The end users demand a predictable and reliable IC performance over a prescribed temperature range. Therefore, designers employed passive and active means to achieve the desired results.
Current techniques utilized in addressing temperature variation have limitations. These limitations include, additional design resources, cost penalties, additional silicon, and/or board area allocation, increased power consumption, etc. An example of a passive means to control the IC temperature, and thus IC performance, can be a heat sink with an air forcing mechanism. This method works well at elevated temperatures, but not at low temperatures. Also, the method stated above requires additional elements, power, area, and has increased cost. An alternative, an active method that can include a temperature stable external reference oscillator coupled to a Phase Locked Loop (PLL). The PLL can provide a stable clock output over temperature variation. The PLL clock output can be used as a reference, and coupled with other circuitry can yield a closed loop system that can adjust for temperature variation. Again, this method requires additional elements, power, die area, design resources, and it is very costly.
Therefore, it is desirable to provide circuits and methods that can enable the end user to employ an IC with minimal consideration to performance degradation due to temperature variation and a cost effective means to employ such circuit on an IC.